第52~54题基于以下叙述:
有关系模式P (A,B,C,D,E,F,G,H,1,J ),根据语义有如下函数依赖集:F
={ABD→E,AB→G,B→F,C→J,C→I,G→H}。
关系模式P的码是()。A.(A,C)B.(A,B,G)C.(A,G)D.(A,B,C,D)
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设在工程中有一个标准模块,其中定义了如下记录类型:Type Books Name As String *10 Te1Num As
执行如下两条语句后,窗体上显示的是 。a=9.8596print Format(a,"$00,00.00")A.0,009.86 B.$9.86 C.9.86 D.$0,009.86
(34)下列事件过程的功能是:建立一个名为Data1的随机文件,存放角度值及这些角度的正弦函数值和余弦函数值,角度为1,2,3,…,90。请在空白处填入适当的内容,将程序补充完整。 Private Type Ang K As Integer Sinx As Single Cosx As Single End Type Dim Ksc As Ang Private Sub Form_Click() Dim Y As Single Dim i As Integer Dim Ksc As Ang Open Y=3.14159/180 For i=1 To 90 Ksc.K=i Ksc.Sinx=Sin(i*Y) Ksc.Cosx=Cos(i*Y) ___________ Next i Close #2 End SubA."‥\Datal.txt"For Random As#1 Len=10 Put#1,i,KscB."‥\Datal.txt"For Random As#1 Len=10 Put#1,Y,Ksc C."‥\Datal.txt"For Random As#1 Put#1,i,KscD."‥\Datal.txt"For Random As#1 Put#1,Y,Ksc